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The Tenth Day of Awesome

For me, one of the most irritating things about woo-mongering is the implication that we need magic and fairy stories to make something awesome. But as this blog as a whole and this series of posts in particular aims to prove, reality is plenty awesome enough on its own.

Today’s example of awesomeness is… Chemistry!

I decided to have a bit of fun today, with a slightly sideways look at the awesomeness of chemistry.

I was the kind of child who was interested in everything at school, especially science and maths, and I think part of the reason that I chose chemistry as a degree/career path was that it’s a very visual subject. Chemistry and chemical reactions are tangible, observable things and this captured my imagination from a very early age.

To see what today’s kids have available to introduce them to the wonders of chemistry, I headed off to town and bought myself a chemistry set!

I was pleasantly surprised by what I found inside the box. The test-tubes and flask were nice, sturdy glass, and there were lots of vials of interesting looking chemicals. There was even a little burner that you fill with methylated spirits. It all looked nice and proper. Oh the possibilities!

I started by playing with copper sulphate, it makes a pleasingly bright blue solution and very pretty crystals.

Copper sulphate crystals forming on the cold surface of a mirror.

One of the experiments suggested in the manual was to heat a few crystals in a test-tube and “note what happens”. So I did. Sure enough, the crystals turn white as they are heated, and if you add a drop of water, they turn blue again. Simple explanation – anhydrous (i.e. dry) copper sulphate is white, and hydrated copper sulphate is blue. This actually illustrates an important chemical point. A lot of crystalline materials can incorporate varying amounts of water in their structure, and this can cause havoc by changing their properties.

Copper sulphate goes from blue to white and back to blue... it's all down to the water content.

I also had a go at test-tube soap making: sodium carbonate and calcium hydroxide were mixed together and dissolved in water to make sodium hydroxide, which was then boiled with some lard and some salt to make a goopy blob of soap. The two-stage transformation was particularly appealing to me, and that’s an important point about chemistry, too. If you have a certain product in mind, you might have to trace back tens, even hundreds of steps to get to a starting material you can work with. Chemistry requires a lot of imagination!

I also enjoyed the various flame tests (the kit includes iron, calcium and sodium salts, but encourages experimentation with household chemicals, food items and even printed text) but then again, I’ve never met a chemist who doesn’t like burning things!

The most “awesome” things I tried were the exchange reactions with zinc and aluminium and copper sulphate. The zinc or aluminium replace the copper in the sulphate and metallic copper precipitates out – magic!

The destruction of aluminium foil in copper sulphate solution leads to the precipitation of metallic copper.

That said, I think this kit would be intensely frustrating to a child, particularly one without a chemistry-literate adult to help. Some of the things I tried could have worked, but didn’t at the concentrations suggested in the instruction booklet. I wouldn’t consider this kit a toy, exactly, because I’ve seen more immediate and fun results from “kitchen chemistry” but for an interested child it would be perfect to push them a little beyond the national curriculum. I was pleased to see that even with today’s crazy attitudes towards safety, a kit with real chemicals, and the fabulously fun spirit burner, still exists and is easily available on the high street! We need lots of kids thinking that chemistry is awesome!

On a final note, here’s something which, until recently, I honestly thought that everyone knew about… the awesomeness of custard. Custard forms something called a non-Newtonian fluid, which has some slightly odd properties. I urge you all to try this yourself: custard powder or cornflour, minimum amount of water, go for it! Here’s a silly video to whet your appetite.

Isn’t chemistry cool?!

The Ninth Day of Awesome

For me, one of the most irritating things about woo-mongering is the implication that we need magic and fairy stories to make something awesome. But as this blog as a whole and this series of posts in particular aims to prove, reality is plenty awesome enough on its own.

Today’s example of awesomeness is… radiation.

Radiation is a bit of a scary word these days, isn’t it? It is probably one of the most consistently misunderstood things on the planet. Five minutes Googling yields an awful lot of shouty articles about the evils of radiation, most of which show absolutely no understanding of what radiation is, and just how many ways it benefits our lives.

There are two distinct classes of radiation: ionising and non-ionising. Ionising radiation, like X-rays, gamma rays and alpha particles, has sufficient energy to displace one or more electrons from an atom, and if this occurs in an atom which is part of a molecule which is part of you, there is a potential for you to be damaged. Non-ionising radiation, such as radio waves and visible light, does not have enough energy to mess with electrons in atoms, though its energy can interact with atoms in other ways.

This post is going to stick to talking about ionising radiation because it’s both more scary and more interesting. In my opinion, implausible theories about the damaging effect of mobile phone radiation or Wi-fi signals are dull, repetitive and well debunked elsewhere.

Let me start by saying that ionising radiation is undeniably dangerous. Short-term, intense exposure can cause burns and long-term exposure is linked to cancer and genetic damage. However, there are other important facts that are often overlooked. First, radiation is not unnatural, or even unusual. We are all exposed to background levels of radiation (from cosmic rays and natural radioactive materials, etc) all the time. Second, the potential of radiation to cause harm is all down to dose, because your body is able to cope with certain amounts.

In my work at ISIS (see the Fifth Day of Awesome) I come into contact with radiation because my samples become radioactive after hanging out in the neutron beam. I monitor the levels using a Geiger counter and the samples are stored in a lead-lined container until they are safe to take away. Even when the sample is “active” I know I can keep myself safe using the simplest of methods, like waiting a few minutes for most of the radiation to decay, keeping them at arm’s length and wearing simple rubber gloves. This is honestly enough to prevent getting myself irradiated. See? It’s not that scary after all.

Let me now say that ionising radiation is equally undeniably, incredibly useful. As well as the obvious importance of nuclear power, the use of X-rays and radioisotopes have revolutionised diagnostic medicine, and the use of radiation therapy for cancer treatment has saved thousands of lives. But there are also other, less obvious and equally awesome uses. Food irradiation can be used to destroy dangerous bacteria like salmonella and extend shelf life, and before anyone asks, it does not make the food radioactive. Chemists and physicists can use radioactive versions of common molecules to follow chemical reactions and biological processes more easily. The understanding gained from these sorts of experiments is a vital part of scientific research and can directly impact medical and industrial innovation. Electron-beam radiation can clean exhaust gases from power stations and industrial plants. Even the humble smoke detector contains a tiny source of radiation.

So for its million uses in medicine, industry, science and more, I award ionising radiation the stamp of awesome!

Sources include:
http://www.iaea.org/nafa/d5/public/foodirradiation.pdf
http://www.gwu.edu/~nsarchiv/radiation/dir/mstreet/commeet/meet1/brief1/br1j.txt